Awhile back, I was sitting on the mat, talking to one of my instructors. In passing, I asked him what his favorite submission was. In true black belt fashion, it wasn't a flying armbar, an inverted 50/50 omoplata to Comprido/toe hold. It wasn't an inverted triangle nor was it an inverted guard sweep to kneebar.
Nope. It was a scissor sweep to mounted collar choke.
In true blue belt fashion, I curiously asked why.
He said that to him, what was great about Roger Gracie was that he dominated world class athletes and competitors with simple basics and make them look like white belts.
He said something to the effect of, "when I mounted collar choke you, I have beaten all of your defenses, I have surpassed all of your knowledge and escapes....and you look me in the face while I put you to sleep, tap, or quit."
Simply put, I have dominated you no differently than a white belt, and choked your bitch ass.
On that note, I found a clip of Roger Teaching his mounted collar choke, and then another from Trumpet Dan (that guy has some great instructional stuff available on youtube for free :) Go check it out.
Roger teaching what he does to elite level players
Trumpet Dan's breaks it down real slow-like